In a system with hardware digital rights management (DRM) processing for protected content, the DRM encrypted audio video (AV) stream is typically decrypted inside a secure embedded processor, for example on graphics processing unit (GPU) hardware, etc. The result is re-encrypted under a symmetric encryption key to insecure memory for consumption by a software player. The symmetric encryption key is shared between the secure embedded processor and the software player via a separate secure key exchange protocol.
Although this system guarantees the security of the video DRM device and sequence keys, as well as the media and title key, a central processing unit (CPU) load may still remain high if an inefficient data representation format is employed for the re-encrypted result of hardware video DRM processing. For example, a naive scheme that re-encrypts the entire AV stream using the Advanced Encryption Standard (AES) would require the software player to decrypt all the data in order to retrieve all non-video packets, as well as to locate all the video headers necessary to correctly schedule decode, render, and display calls.
There is thus a need for addressing these and/or other issues associated with the prior art.